Objective: Low- and middle-income countries are experiencing rises in the prevalence of adult obesity. Whether these increases disproportionately affect vulnerable subpopulations is unclear because most previous investigations were not nationally representative, were limited to women, or relied on self-reported anthropometric data which are subject to bias. The aim of the present study was to assess changes in the prevalence of obesity from 2005 to 2010 in Colombian adults; overall and by levels of sociodemographic characteristics.Design: Two cross-sectional, nationally representative surveys.Setting: Colombia.Subjects: Men and women 18–64 years old (n 31 105 in 2005; n 81 115 in 2010).Results: The prevalence of obesity (BMI ≥30 kg/m²) was 13·9 % in 2005 and 16·4 % in 2010 (prevalence difference = 2·7 %; 95 % CI 1·9, 3·4 %). In multivariable analyses, obesity was positively associated with female sex, age, wealth, and living in the Pacific or National Territories regions in each year. In 2010, obesity was also associated with living in an urban area. The change in the prevalence of obesity from 2005 to 2010 varied significantly according to wealth; 5·0 % (95 % CI 3·3, 6·7 %) among the poorest and 0·3 % (95 % CI −1·6, 2·2 %) in the wealthiest (P, test for interaction = 0·007), after adjustment. Obesity rates also increased faster in older than younger people (P, test for interaction = 0·01), among people from urban compared with non-urban areas (P, test for interaction = 0·06) and in adults living in the Atlantic region compared with others.Conclusions: Adult obesity prevalence has increased in Colombia and its burden is shifting towards the poor and urban populations.

Objective: To develop a food-frequency questionnaire (FFQ) useful for ranking of nutrient intakes.Design: Subjects consuming their regular diet completed 7 days of weighed intake registry (7-WIR). Foods for the FFQ were selected by stepwise multiple regression. The FFQ was then completed for each subject using data on individual food consumption from the 7-WIR. The correlation and agreement between the extrapolated FFQ and the 7-WIR data were assessed using Spearman's rank correlation coefficients (r_S) and Bland and Altman's limits of agreement (LOA).Setting: Bucaramanga, Colombia.Subjects: We studied 97 randomly selected 20–40-year-old subjects.Results: Sixty foods were selected for the FFQ. The 7-WIR and the extrapolated FFQ intake estimates correlated well. r_S was 0.58 for energy, 0.53 for carbohydrate, 0.50 for total fat, and 0.48 for protein. For micronutrients, r_S varied from 0.46 (manganese) to 0.71 (vitamin B₁₂). FFQ average intake estimates were 83%, 80%, 86.2% and 86.4% of 7-WIR estimates for energy, carbohydrate, total fat and protein, respectively. LOA for these nutrients ranged between 45% and 165%. FFQ micronutrient intakes were on average 96% (median) of those from the 7-WIR, and the median lower and upper LOA were 50% and 203%. However, there was no indication that the degree of agreement varied with the level of intake.Conclusions: According to our simulated validation, this FFQ may be useful to rank subjects by nutrient intake. Its validity against standard independent measurements and its applicability to other subsets of the Colombian population should be carefully considered.

SUMMARY: Vitamin D could modulate pathways leading to dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). We examined the associations of serum total 25-hydroxy vitamin D [25(OH)D] and vitamin D binding protein (VDBP) concentrations in patients with uncomplicated dengue fever (DF) with risk of progression to DHF/DSS. In a case–control study nested in a cohort of DF patients who were followed during the acute episode in Bucaramanga, Colombia, we compared 25(OH)D and VDBP at onset of fever between 110 cases who progressed to DHF/DSS and 235 DF controls who did not progress. 25(OH)D concentrations were also compared between the acute sample and a sample collected >1 year post-convalescence in a subgroup. Compared with 25(OH)D ⩾75 nmol/l, adjusted odds ratios (95% CI) for progression were 0·44 (0·22–0·88) and 0·13 (0·02–1·05) for 50 to 75 nmol/l (vitamin D insufficiency) and <50 nmol/l (vitamin D deficiency), respectively (P, trend = 0·003). Mean 25(OH)D concentrations were much lower post-convalescence compared with the acute episode, regardless of case status. Compared with controls, mean VDBP was non-significantly lower in cases. We conclude that low serum 25(OH)D concentrations in DF patients predict decreased odds of progression to DHF/DSS.

PUFA might modulate inflammatory responses involved in the development of severe dengue. We aimed to examine whether serum PUFA concentrations in patients diagnosed with dengue fever (DF) were related to the risk of progression to dengue haemorrhagic fever/dengue shock syndrome (DHF/DSS). A secondary aim was to assess correlations between fatty acids (FA) and inflammatory biomarkers in patients with DF. We conducted a prospective case–control study nested within a cohort of patients who were diagnosed with DF and followed during the acute episode. We compared the distribution of individual FA (% of total FA) at onset of fever between 109 cases who progressed to DHF/DSS and 235 DF non-progressing controls using unconditional logistic regression. We estimated correlations between baseline FA and cytokine concentrations and compared FA concentrations between the acute episode and >1 year post-convalescence in a subgroup. DHA was positively related to progression to DHF/DSS (multivariable adjusted OR (AOR) for DHA in quintile 5v. 1=5·34, 95 % CI 2·03, 14·1;P_trend=0·007). Dihomo-γ-linolenic acid (DGLA) was inversely associated with progression (AOR for quintile 5v. 1=0·30, 95 % CI 0·13, 0·69;P_trend=0·007). Pentadecanoic acid concentrations were inversely related to DHF/DSS. Correlations of PUFA with cytokines at baseline were low. PUFA were lower during the acute episode than in a disease-free period. In conclusion, serum DHA in patients with DF predicts higher odds of progression to DHF/DSS whereas DGLA and pentadecanoic acid predict lower odds.